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Thread: What is S7 steel?
06-12-2006, 09:36 PM #1
And what would be uses? They are throwing away almost all the toolsteel at work.I was digging through the hopper and found some blocks and bars of S7.Lots of D2 and A2 an and A7.What a waste!
06-12-2006, 09:49 PM #2
IMHO, S-7 is one of the best tool steels , for general- purpose work. Top RC hardness is around 57-59, it is very stable, machines well. I always preferred keeping it below 55 RC, it is notch-sensitive (Cracks) above that... One brand of S-7, known as "Bearcat", is reputed to have slightly different characteristics than that from other mills, but I have used it with no ill effects.. If you can, it would be worth grabbing all that steel up...
06-12-2006, 09:52 PM #3
AISI SAE S-7 Hi Shock Drill rod.
Shock resistant tool steel for hot-work applications up to 1000deg F.
Great for chisels, cutting and striking tools.
Maybe press brake tooling? Punches?
High strength with good ductility.
Heat treat up to 59-61 HRc.
Preheat to 1200-1300, then raise to 1725deg F.
hold for one hour, quench in still air.
Draw back and temper upon reaching 150 deg.
Tempering range 1300 to 400.
06-12-2006, 10:12 PM #4
Wow that was quick.I didnt know how it machined so I didnt grab it.I guess I need to dig out some.We dont do die work anymore and that is why the cleanup.I remember machining "chromewear" years ago.It has another ID but always remembered that name.Hated to machine that stuff.Now that I think about it I believe it was the same as A7.Anyone know? I drug some A7 home also.Dont really like that tuff stuff.I dont want to tear up my tooling.
06-12-2006, 10:18 PM #5
S7 is one of the nicer machining tool steels I use. Almost like W1. It is airhardening, so responds best to heat treating in a furnace with controlled temperatures and soak. (as opposed to torch). I use foil wrap.
06-12-2006, 10:23 PM #6
Dig it out and send it our way !!
06-12-2006, 10:28 PM #7
06-12-2006, 10:31 PM #8
Good abrasion resistance too if I remember correctly. When I was doing moldwork we use a lot of it on cams, slides, and other mechanical devices in molds.
06-12-2006, 10:32 PM #9
S7 used for good ht properties (air), and good shock resistance.
what sizes, as if for sale?
06-12-2006, 10:35 PM #10
YEah, we ust it alot in Injection molds too...usually around 50 Rockwell...Hardmills nice there too...For dies, lightweight we have used it, but A2 or D2 is better for harder steels(like Blue temper or SS)...
It is expensive, as long as it is marked, get it....makes great tools for your box.. [img]smile.gif[/img]
06-13-2006, 03:02 AM #11
It's also popular for air planishing and power hammer dies.
06-16-2007, 10:26 AM #12
Any help on the best anti-shear tool steel?
I'm making a .25 dia round bar screen with 1" square openings. 30" square.
What supplier can supply me?
06-16-2007, 10:35 AM #13
Get all th tool steel they will let you have(or pay for) and figure it out later!!
06-16-2007, 11:54 AM #14
06-16-2007, 05:03 PM #15
we always oil quench the s7. temper at 400. we use it for stamping dies and any other thing that sees an impact. with carbide cut it at 180 sfm. hss and drill 60 sfm. I think it would be suitable for parallels, 123 blocks, v blocks and that type of stuff. it tends to warp a bit during heat treat, so if you're gonna make guage type stuff you would need finishing after heat treat.
I have heard it described as shock resistant chromoly.
06-22-2007, 09:10 PM #16
How can a shop afford to toss tool steel ? Amazing.
S7 is a nice tough one. We used it for punching 5/8 - 3/4" thick chain links. It would last for a good while better than A2 or D2.
But HOW can they toss tool steel ?
06-22-2007, 09:39 PM #17
My power hammer dies are S7 and they take abuse! If you need a home for that stuff just let me know, it is the best for forge work. H13 is good too for tooling in contact with heated iron for long periods such as under hydraulic equipment.
06-22-2007, 09:56 PM #18
Actually we use S-7 for the air hardening qualities, old PWA prints called for S-1 often we offered exeptions to S-7 becuase of the better mechanical properties and ....of course that S-1 is not so readily available anymore . Distortion is very low.
07-12-2007, 12:27 AM #19
Big chunks could make a nice machinist/ toolmakers vise if you have a surface grinder to finish grind it after heat treat.
07-12-2007, 06:59 PM #20
I bought about 100 lbs. of air tool chisels from a local surplus place for a few dollars. Mostly the tangs were broken or deformed. Probably quality rejects. My daughter who was a manager of a chemical analysis lab at the time ran an analysis of the steel and it matched S-7 specs. I am to say the least very happy with that purchase.